(JTA) – Clashes broke out near Ramallah between Palestinians marking Nakba Day, referring to their perception of Israel’s founding as a catastrophe, and Israeli troops.

Eleven Palestinians were injured Monday in the fighting at a checkpoint near the seat of the Palestinian Authority after Israeli soldiers fired rubber bullets and used other riot control measures in response to dozens of Palestinian youths throwing rocks at them.

Also on Monday, thousands of Palestinians marched through Ramallah carrying Palestinian flags and waving keys to symbolize their former homes in Israel before 1948.

Palestinians in the West Bank and Gaza, as well as Arabs around the world held rallies, marches and candlelight vigils to mark the day, which is marked each year on May 15. Each year, a siren is sounded throughout the West Bank for one second for every year since the Nakba. This year, a siren was sounded for 69 seconds as cars stopped and people stood at attention.

On Sunday Marwan Barghouti, the high-profile Palestinian prisoner leading a hunger strike, issued a letter calling on Palestinians to carry out acts of “civil disobedience” on Nakba Day.

Gaza Palestinian fishing boats on Sunday night and Monday attempted to breach a buffer zone of Israel’s coast set up by Israel’s Navy. The boats were fired on Monday morning, leading to the death of one of the Palestinian fishermen, according to the Palestinians’ Maan news agency.

Saeb Erekat, the PLO’s secretary-general and the chief Palestinian peace negotiator, in a statement issued Sunday said that Israeli recognition and apology for the Nakba were a necessary condition “to achieve a just and lasting peace between Israel and Palestine.”

“We call upon the Israeli government to open all its 1948 archives and show their own nation the truth of what was done to our people, including its ethnic cleansing policies and the policy of shooting to kill Palestinians that attempted to return home,” Erekat said.

He also called on Britain to apologize for the 1917 Balfour Declaration that led to the creation of a Jewish state.